# Relationship history for MSHA mine 0405396

Current hierarchy: **Lassen County-Ca → Lassen County Department Of Public Works → RC-2 Portable Rock Crusher**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Lassen County Department Of Public Works → RC-2 Portable Rock Crusher; 1999-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lassen County-Ca → RC-2 Portable Rock Crusher; 1999-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lassen County-Ca → Lassen County Department Of Public Works; 1999-12-01 to current/open; source msha-controller-operator-history